Resersch On The Simulation And Circuit Of The Flyback Micro Solar Inverter

In recent years, with the development of technology and the progress of society, energy shortage has got more and more people’s attention. So developing new energy become the hot topic nowadays. New energy is also called unconventional energy, such as solar energy、wind energy、geothermal energy、ocean energy and etc. Among them, solar energy is a kind of clean renewable energy, developing solar energy is useful for easing the current energy crisis and environment crisis, PV grid connected generation system is an effective way to take use of the solar energy. Otherwise inverter technology is essential technique in the photovoltaic generation system, there is an micro inverter in each photovoltaic cell, which can improve the grid-connected efficiency. Therefore it’s valuable to research the micro photovoltaic inverter.At first, the structure and characters of the inverter have been introduced. Then the do-mestic and foreign research present situation micro inverter and the topology structure have been analyzed, a suitable and efficient inverter structure has been presented in this paper.The the way to control the micro inverter grid -connected is analyzed in detail, a new control way is introduced into this paper.Then the circuit of the inverter has been analyzed, its working principle is introduced, the math mode is build. After this, transformer parameter, the output and input capacitors is cal-culated, the matlab/simulink model of inverter has been build, and the controlled to control pre-current is designed. In order to improve the efficiency of micro inverter, the simulation of the inverter is modified to build the double-current control model, and the feasibility is proved.Due to the PI controller can’t restrain the harmonics effectively, especially the harmonics at the zero-crossing. Therefore the PI multi-resonance is introduced into the controller. Then according to root locus method to design the parameters of the PI multi-resonance, simulation is used to prove the feasibility of the parameters. Except that, different resonance ways is re-searched and analyzed. The simulations of resonance, multi-resonance, PI resonance is built, then grid-connected current harmonic is analyzed.At last, according to the topology structure of the inverter, the hardware circuit of the photovoltaic inverter is designed. The control circuit and drive circuits of the inverter is de-signed. According to the inverter’s whole structure, the whole function of the inverter is in- troduced by the way all part circuits. And the function attribution of the control microchip is analyzed, then the hardware work principle is described.